Looking at this I think the creature base could be improved some as well, I like a lot of your choices,
Ohhh makes sense, I'm starting to work on my Abzan Toughness deck. Turning Tower defense into an insane instant speed 2 mana Overrun??? Yes please.
Hrm, seems like a fine list to start with, you have a lot of power in the deck, Iona, Avacyn, Sun Titan, boop ghost though as the deck is now it doesn't exactly scream like a Eight tails list it seems more like a big white deck with tokens and angels. If you want ideas on what to work with in your deck I use EDHrec, it helped wonders with my Brion list. http://tappedout.net/mtg-decks/throw-your-problems-at-your-problems/